BMW's M30 "Big Six" went into plenty of 5-, 6-, and 7-series BMWs (not to mention the E9), starting in 1968, and did a great job of setting the standard for serious inline-six performance.However ...

This 1985 BMW 535i is the grandfather of the current M5, ... 3HP22 – common on both six-cylinder versions of the E28 5 Series – which was available with both the M20 and the M30 engines.

In this series, we'd like to honor the engines that were made in vast quantities and/or remained in front-line service for decades (in addition to low-production Ass-Kickin' Engines), and the BMW ...